Indicating device for mechanical pencils



Jan. 18, 1944. w. o PONATH mnxca'rme DEVICE FOR MECHANICAL PENCILS Filed June 6. 1941 mm w I'll? u. 0 8 Mm 1 Patented Jan. 18, 1944 INDICATING' DEVICE FOR MECHANICAL PENCILS William 0. Ponath, Richmond Hill, N. Y., assignor to Eagle Pencil Company Inc., New York, N. Y., a corporation of Delaware' ApplicationrJune 6, 1941, Serial No. 396,840

10' Claims.

The present invention relates more especially to that general type of drafting pencil in which a clutch serves releasably to retain the lead, and is especially concerned with means on the case of such pencil, which is readily set by the draftsman to indicate the hardness or grade of the lead installed therein.

An object of the invention is to provide index means of the type noted, at the upper end of the pencil case, which shall be of simple inexpensive and rugged construction, which may readily be set to identify any lead with which the pencil is charged, which setting is not subject'to fortuitous shifting and which may be so correlated with the shaft of the pencil that torque may be applied thereon for the operation of the clutch at the opposite or point end of the pencil.

The present invention is a continuation in part of my copending application Serial No. 310,765, filed December 23, 1939, Patent No. 2,262,6 l9 issued November 11, 1941.

In the accompanying drawing in which are shown one or more of various possible embodiments of the several features of the invention,

Fig. l is a side elevation showing the general outline of a preferred form of pencil,

Fig. 2 is a view in longitudinal cross-section of the upper end of such pencil taken on line 2-2 of Fig. l and on a larger scale,

Fig. 3 is a transverse sectional view taken on line 3- 3 of Fig. 2,

Fig. 4 is a transverse sectional view taken on line *L- l of Fig. 2, v

Fig. 5 is a. dropped perspective view of the ele ments making up the assembly of Fig. 2,

Fig. 6 is a longitudinal sectional view showing parts in perspective of an alternative embodiment of cap member,

Fig.7 is a fragmentary perspective view showing the pencil end with which the cap of Fig. 6 would cooperate, and

Fig. 8 is a perspective view of an alternative form of index barrel.

Referring now to the drawing there is shown in Fig. l the general outline of the clutch pencil in question. It need not be described in detail since its general structure is conventional, and its preferred development is the subject of the prior application above-identified; It may be briefly noted here that the case Whats a metal tip H coacting with the clutch l2 which grips the forward end of the replaceable lead l-S that ex tendssuostantially the length of the pencil case or shaft.

At the upper end of'the pencil shaft is mounted the indicator construction Iillustratively set to display through the window the correct designation l5. corresponding to the lead which the draftsman has installed in the case.

In the detailed embodiment of Figs. 2 to l, the case Ill is illustratively shownof metal, although of course it. might be vof wood, as illustratively shown in the earlier application. Telescoped and securely and'irremovably fitted into the upper end of the metal case. is a bushing 16 with a fiat shoulder l1 flush with the upper edge of the case andhaving a unitary tubular mounting extension it? of reduced diameter; A solid metal ring. l9 desirably encircles the bushing extension I8 and snugly engages the shoulder ll of the bushing and the upper edge of the case l0 flush therewith. The ring I!) may be conformed to present an ornamental peripheral bead serving as atrim for the pencil.

Encircling the lower part of the extension mount I8 is a ferrule 20, frictionally fitted thereover and engaging the ring l9 at itslower end. Ferrule 20 preferably has longitudinal ribs 2i desirably three in number, pressed out therefrom,. extending longitudinally thereof, and spaced. by uniform. angular intervals. The ferrule 29 serves as, the mount for the index barrel 22. That barrel has an outer polygonal conformation, desirably hexagonal, and its flats bear respectively, difierent indices corresponding to the lead grades as shown. The internal hexagonal bore of the index barrel is such that when telescoped over the ferrule, H! as shown in Fig. 4 the ribs 21 will be snugly and frictionally retained in alternate apices of said barrel. This arrangement holds the index barrel 22 against rotarymov'ement'but the frictional hold thereof on the ribs 2| permits it to be axially removed and replaced by another similar index barrel bearing a. different range of lead grades where this is desired. 1

Telescoped over the index barrel 22 is a window cap C having. an outer section 25 desirably of bone and with a bushing 26 therein desirably of brass, press fitted or molded in the inside of said bone section. The bushing 25 may desirably have a unitary ornamental beaded conformation 27 against which the bone section 25-bottoms and a sleeve or skirt section 28 unitary therewith of length corresponding to that of the index barrel 22. The skirt 28 is provided with a generally rectangular window opening, l4 through which the index l5 at the outer flats of the index barrel 22 may be selectively exposed as shown. Desirably. the, window capC- is; lined with a metal bushing 30 having longitudinal ribs 31 pressed thereinto which frictionally grip the upper end of the mounting extension l8 and thereby frictionally retain the cap in position upon the pencil case, without the need for any frictional hold of the skirt 28 upon the index barrel 22.

Thus the window cap may be readily set to indicate the particular grade of-lead in the case, the latter serving as a universal lead holder which at a glance will designate the particular grade of lead that the draftsman has installed therein; There is no danger of inadvertent shift of the grade exposed. Throughout use of the pencilthe indicating end remains a rigid part. of the case.

In fact it can be used as the handle for.

ing for exposing therethrough the selected index, and means unitary with said sleeve and beyond the outer end of said index member for releasably gripping the pencil and retaining said sleeve in place.

her, said respective members having mutually interlockin conformations preventing relative setting, tightening or adjusting the clutch l2 at the lead end of the unit.

In Figs. 6 and 7 as shown inan alternative embodiment, the ferrule 35 extends the entire length of the mounting extension I8 to which it is securely and irremovably anchored by' soldering or welding if such bushing is ofmetal, or by indentation thereinto in convenient manner where the sleeve is of wood. The index'barrel 22 similar to barrel 22 is telescoped over ferrule 35. It is releasably locked in position by a rectangular locking tongue 36 stamped out of the ferrule by longitudinal slots at opposite sides of one of the ribs 31 and a connecting transverse slot. This tongue 39 is bent outward slightly and acts as shown in Fig. '7 to latch the upper edge of the index barrel 22' upon the ferrule. The index barrel may however readily be removed whenever desired by simply pressing the tongue 36 inward against the mounting extension l8, so that the index barrel may be readily slid thereover for replacement by another index barrel. Of course the mounting extension l8 serves as a stop to prevent the-locking tongue 36 from being forced inward below the surface of the case.

The ribs 31 at the upper end of the ferrule 35 serve in this-embodiment as the means for frictionally anchoring the Window cap in position. Accordingly the metal liner 30' of the window cap C'- may be devoid of the ribs .31 provided in the additional liner used in the embodiment of Figs. 2 to 5.

Instead of the two interchangeable index barrels of Figs. and 7 it may be desirable as shown in Fig. 8 to employ a single index barrel 40 having two tiers of indicia, one of which, tier 40 bears those grade marks that are less frequently used.- Thus no extra index barrel need be kept in reserve and a large choice of indicia is available. Of course the use of the embodiment oi Fig. 8 would require corresponding elongations of the tip. I

As many changes could be made in the above construction and many apparently widely different embodiments of this invention could be made without departing from the scope .ofthe claims, it is intended that allmatter contained in the above description or shown in the. accompanying drawing shall be interpreted as illustrative and not in a limiting sense. I

Having thus described my invention, what I claim as new and desire to secure by LettersPatentis: I H

1. An indicating device for a pencil, including apolygonal index member with diverse indices on the respective sides thereof; and a sleeve telescoped over said index'member and having an internal bore of corresponding polygonal crosssectiomsaid sleeve havinga single windowopenrotation thereof, while permitting relative axial movement thereof, and a sleeve telescoped over said index member, and having a single window for exposing therethrough the selected index said sleeve having unitary means for retaining the same in placeupon said supporting member.

3. An indicating device for a mechanical pencil, including a tubular index member bearin a series of indices circumferentially spaced on its outer surface, and having a bore of polygonal cross-section extending longitudinall thereof, a supporting member for said index member passing through the same, and having ribs extending longitudinally thereof and into certain of the apices of said bore, whereby said members are interlocked against relative rotation, but are per mitted to be moved relatively in the axial direction, and a sleeve telescoped over and extending beyond said index member and frictionall held upon said supporting member, and having a window for exposing therethrough the selected index.

4. An indicating device for a pencil case with replaceable lead, including a mount at the upper end of the case, an index carrying polygonal sleeve about said mount said mount having an extension beyond said sleeve, and a window cap frictionally affixed to said extension at the outer.

part thereof and having a skirt unitary therewith overlapping said index carrying sleeve and selectively exposing one of the diverse indications of the index sleeve and abutting the base end of said mount.

5. In a pencil of the type having a selectively replaceable grade of lead, comprising a pencil case, an axial mountin extension, a stop piece at the base of said extension, a polygonal index barrel keyed to the base end of said mounting extension and a Window cap piece removably telescoped over said extension, having a skirt with a polygonal bore correspondin to that of said index barrel and having a Window therein selectively to expose one of the indicia on said barrel, the upper end of said window cap havin a frictional grip upon the outer end of said mounting extension.

6. An indicating device for a pencil of the type having replaceable leads, comprising a bushing fitted into the metal case of such pencil and having a reduced indicia mounting cylindrical extension, a bottoming ring encircling said extension and overlapping the edge of said case, a ferrule of length shorter than the mounting extension telescoped over the end thereof and having equidistant longitudinal ribs protruding outward therefrom, a hexagonal index barrel frictionally gripped at alternate vertices by said ribs and a Window cap having a bushing in the upper end thereof with ribs frictionally engaging the outer part of said mounting extension and having a skirt unitary therewith and abutting against said ring, said skirt having a hexagonal bore to fit overthe index barrel, saidskirt having a window,

therein selectively to expose one index on said index barrel.

7. In combination with a mechanical pencil having a shaft, a metal ferrule snugly fitted over the end thereof, and having a tongue longitudinally thereof presenting a slightly protruding forward edge and a metal index barrel removably telescoped over said ferrule and latched by the forward end of said tongue, and a window cap member comprising a metal sleeve removably telescoped over said ferrule and said index barrel and presenting a window for a face of said barrel, said sleeve having a closure at its upper end.

8. In combination with a mechanical pencil having a shaft, a metal ferrule snugly fitted over the end thereof, and havin a tongue longitudinally thereof presenting a slightly protruding forward edge, a metal index barrel removably telescoped over said ferrule and latched by the forward end of said tongue, and a window cap member comprising a metal sleeve removably telescoped over said ferrule and said index barrel and presenting a window for a face of said barrel, the outer end of said sleeve being of reduced diameter and having a cap of bone or the like firmly telescoped thereover.

9. The combination recited in claim 8 in which the index barrel has two' tiers of indices for selective application to the pencil with the lowermost tier in line with the window of the window cap member.

10. In combination with a mechanical pencil having a shaft, an index barrel of regular polygonal cross-section having two tiers of indices on the faces thereof, means releasably to retain the index barrel upon the pencil with either end outermost, and a window cap member releasably telescoped over said sleeve, having a window aligned with One of the tiers of indices, selectively to expose to view when in place any index on the tier aligned therewith.

WILLIAM C. PONATH. 

